Add the ability for nm to display symbol version information.

PR binutils/20751
	* nm.c (with_symbol_versions): New local variable.
	(long_options): Add --with-symbol-versions.
	(usage): Mention --with-symbol-versions.
	(print_symbol): If with_symbol_versions is set then display the
	version information associated with the symbol.
	* NEWS: Mention the new feature.
	* doc/binutils.texi (nm): Document the new option.
	(objdump): Describe how symbol version information is displayed
	for dynamic symbol dumps.
	(readelf): Describe how symbol version information is displayed.
	* testsuite/binutils-all/nm.exp: Add a test of the new feature.

binutils/testsuite/binutils-all/nm-ver.s

@@ -0,0 +1,9 @@
+	.symver foo_old,foo@VER_1
+	.hidden foo_old
+foo_old:
+	.dc.b 0
+
+	.symver foo_new,foo@@VER_2
+	.global foo_new
+foo_new:
+	.dc.b 0

binutils/testsuite/binutils-all/nm.exp

@@ -207,4 +207,35 @@ if [regexp $want $got] then {
     fail "nm --size-sort"
 }
 
+if [is_elf_format] {
+    # PR binutils/20751
+    # Test nm --with-symbol-versions
+
+    if {![binutils_assemble $srcdir/$subdir/nm-ver.s tmpdir/nm-ver.o]} then {
+	fail "nm --with-symbol-versions (assembling)"
+    } else {
+	if [is_remote host] {
+	    set tmpfile [remote_download host tmpdir/nm-ver.o]
+	} else {
+	    set tmpfile tmpdir/nm-ver.o
+	}
+	
+	set got [binutils_run $NM "$NMFLAGS --with-symbol-versions --format sysv $tmpfile"]
+
+	if {! [regexp "foo@VER_1" $got]} then {
+	    fail "nm --with-symbol-versions (grep for @VER_1)"
+	} else {
+	    if {! [regexp "foo@VER_1" $got]} then {
+		fail "nm --with-symbol-versions (grep for @@VER_2)"
+	    } else {
+		pass "nm --with-symbol-versions"
+	    }
+	}
+
+	if { $verbose < 1 } {
+	    remote_file host delete "tmpdir/nm-ver.o"
+	}
+    }
+}
+
 # There are certainly other tests that could be run.